Axes - R Graphics - page 230

Removing Tick Marks and Labels

Problem
You want to remove tick marks and labels.

Solution
To remove just the tick labels, as in Figure 8-14 (left), use theme(axis.text.y = ele-
ment_blank()) (or do the same for axis.text.x ). This will work for both continuous and
categorical axes:

p <- ggplot(PlantGrowth, aes(x = group, y = weight)) + geom_boxplot()

p + theme(axis.text.y = element_blank())

Figure 8-14. Left: no tick labels on y-axis; middle: no tick marks and no tick labels on y-axis; right:
with breaks=NULL

To remove the tick marks, use theme(axis.ticks=element_blank()) . This will remove the
tick marks on both axes. (It's not possible to hide the tick marks on just one axis.) In this ex-
ample, we'll hide all tick marks as well as the ytick labels ( Figure 8-14 , center):

p + theme(axis.ticks = element_blank(), axis.text.y = element_blank())

To remove the tick marks, the labels, and the grid lines, set breaks to NULL ( Figure 8-14 , right):

p + scale_y_continuous(breaks = NULL NULL )

This will work for continuous axes only; if you remove items from a categorical axis using lim-
its , as in Changing the Order of Items on a Categorical Axis , the data with that value won't be
shown at all.